1. Technical Field
The present disclosure relates to a system, apparatus, and method of navigation and position confirmation for surgical procedures. More particularly, the present disclosure relates to a system and method of finding fluoroscope projection variables (angles, focal point, zoom, etc.) relative to a CT in order to extract relevant data from the CT and overlay it on a fluoroscopic image.
2. Discussion of Related Art
Visualization techniques related to visualizing a patient's lungs have been developed so as to help clinicians perform diagnoses and/or surgeries on the patient's lungs. Visualization is especially important for identifying a location of a diseased region. Further, when treating the diseased region, additional emphasis is given to identification of the particular location of the diseased region so that a surgical operation is performed at the correct location.
For example in the lungs, endobronchial navigation systems have been developed that use CT image data to create a navigation plan to facilitate advancing a navigation catheter (or other suitable device) through a bronchoscope and a branch of the bronchus of a patient to the area of interest. Endobronchial navigation may be employed both in the diagnostic (i.e., biopsy) phase and the treatment phases. Electromagnetic tracking may be utilized in conjunction with the CT data to facilitate guiding the navigation catheter through the branch of the bronchus to the area of interest. In certain instances, the navigation catheter may be positioned within one of the airways of the branched luminal networks adjacent to or within the area of interest to provide access for one or more medical instruments. However, the CT data is not used in real time due to the rendering times and the radiation hazard to the users in the vicinity.
Once the navigation catheter is in position, fluoroscopy may be used to visualize medical instruments including biopsy tools, such as, for example, brushes, needles and forceps, as well as treatment tools such as an ablation catheter, as they are passed through the navigation catheter and into the lung and to the area of interest in real time. Conventional fluoroscopy is widely used during medical procedures as a visualization imaging tool for guiding medical instruments inside the human body. Although medical instruments like catheters, biopsy tools, etc., are clearly visible on a fluoroscopic picture, organic features such as soft tissue, blood vessels, suspicious tumor lesions etc., are either somewhat or completely transparent and thus hard to identify with conventional fluoroscopy. Moreover, fluoroscopic images render flat 2D images on which it can be somewhat challenging to assess three-dimensional position of the medical instrument. As such, the clinician is not provided all the information that could be desired to visualize the placement of the medical device within the patient's body relative to the area of interest.
Pose estimation methods are known, but such methods have limitations. For instance, there may be an eventual absence of solution due to non-convergence or the convergence leads to a wrong solution. There is no upper bound to the computing time. Some methods need to use 4 points and there exists geometric constraints on these points, in particular relatively to co-planarity. There may be a difficulty in debugging failures in an intuitive way. Further, some methods require a precise camera calibration.